Bumper absorber for protecting pedestrians

ABSTRACT

A bumper absorber for protecting pedestrians is formed into a W-shaped cross-sectional configuration, as taken along a direction which is orthogonal to a longitudinal direction of the bumper absorber. The W-shaped cross sectional configuration has portions in which a front notch portion, an upper rear notch portion, and a lower rear notch portion overlap with one another in a vertical direction of a vehicle. Ribs are formed respectively at the upper rear notch portion and the lower rear notch portion, and a triangular notch is formed from a vehicle rear side at each of the rib. Further, the ribs  30  are formed at the upper rear notch portion and the lower rear notch portion so as to be separated from each other at predetermined intervals in a longitudinal direction of the bumper absorber, namely, in a transverse direction of the vehicle. With this structure, a rise in impact load acting on a pedestrian who is hit by a bumper can be controlled.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. application Ser.No. 10/529,739, filed on Mar. 29, 2005 now U.S. Pat. No. 7,226,097,which is incorporated by reference in its entirety. application Ser. No.10/529,739 is a national phase application of PCT/JP03/012496, filed onSep. 30, 2003, which is incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a bumper absorber for protectingpedestrians, and more particularly, to a bumper absorber for protectingpedestrians at the time of collision when a pedestrian is hit by avehicle such as an automobile.

2. Description of the Related Art

Conventionally, it has been known that a bumper absorber for a vehiclesuch as an automobile is structured such that an energy absorber made ofa foam is formed into a substantially I-shaped cross-sectionalconfiguration, which aims both to protect pedestrians and to realize alevel of performance which is traditionally demanded of a bumper (forexample, Japanese Patent Application Laid-Open No. 60-37457).

However, with the aforementioned bumper absorber, when a load is appliedfrom a vehicle front to the bumper absorber at a time of collision, anupper wall portion and a lower wall portion of the energy absorberhaving a substantially I-shaped cross-sectional configuration arecompressed and deformed into a vehicle longitudinal direction. As aresult, a rise in the initial load level is subdued, and the amount ofenergy absorbed decreases.

Therefore, a bumper absorber for protecting pedestrians is desirable inwhich a load level rises immediately at an initial stage when a load isapplied to the bumper absorber, that is, when a pedestrian is hit by abumper.

In another type of conventional bumper absorber, as shown in FIG. 28, abumper absorber (also referred to as an “energy absorber”) 104 is housedin a bumper cover 102 (also referred to as a “shell”) of a bumper 100.The bumper absorber 104, as seen from a direction which is orthogonal toa longitudinal direction of the bumper absorber 104, is formed into alopsided U-shaped cross-sectional configuration in which an openingportion 106 is formed to face a vehicle front. The bumper absorber 104is also provided with a vehicle rear portion 104A in which a pluralityof convex portions 108 is formed to face a vehicle rear and the vehiclerear portion 104A is fixed to a bumper reinforcement (also referred toas a “mounting means”) 110 (for example, JP-A No. 57-47234).

However, with the aforementioned bumper absorber 104, when, at the timeof a collision, a load is applied from the vehicle front to the bumperabsorber 104, as shown by a chain double-dashed line in FIG. 28, anupper wall portion 104B and a lower wall portion 104C of the bumperabsorber 104 are compressed and deformed in a vehicle longitudinaldirection. As a result, in direct relation to the rate of compression atwhich the bumper absorber 104 is compressed, there is a proportionaterise in impact load applied by the bumper absorber 104 on a pedestrianhit by the bumper.

In view of the aforementioned facts, an object of the present inventionis to provide a bumper absorber for protecting pedestrians in which aload level can be swiftly raised at an initial stage when a load isapplied to the bumper absorber, that is, when a pedestrian is hit by abumper and in which a rise in an impact load acting on a pedestrian whois hit by the bumper can also be controlled.

SUMMARY OF THE INVENTION

In order to solve the above-described problems, one embodiment of thepresent invention relates to a bumper absorber for protectingpedestrians, which is disposed in a bumper cover with a longitudinaldirection of the bumper absorber for protecting pedestrians disposedalong a vehicle transverse direction and which is formed by a foam forabsorbing impact energy, characterized in that a cross-sectionalconfiguration which is orthogonal to the longitudinal direction of thebumper absorber for protecting pedestrians is formed into a shape havinga portion in which a front notch portion notched from a vehicle frontside and rear notch portions notched from a vehicle rear side overlapwith one another in a vehicle vertical direction, and the bumperabsorber for protecting pedestrians has opening means for opening, whena load having a predetermined value or higher is applied from thevehicle front to the bumper absorber for protecting pedestrians, anupper wall portion in an upper direction and for opening a lower wallportion in a lower direction.

Therefore, when, at the time of a collision, a load having apredetermined value or higher is applied from the vehicle front to thebumper absorber, with an operation of the opening means, the front notchportion and the rear notch portions are opened, and the upper wallportion and the lower wall portion of the bumper absorber extend in thevehicle vertical direction upward and downwards, respectively.Accordingly, the upper wall portion and the lower wall portion of thebumper absorber are not compressed and deformed in the vehiclelongitudinal (front-rear) direction. As a result, a rise in an impactload applied by the bumper absorber on a body into which the vehiclecollides (i.e., a pedestrian who is hit by a bumper) can be controlled.

Another embodiment of the present invention is a bumper absorber forprotecting pedestrians, which is disposed in a bumper cover with alongitudinal direction of the bumper absorber for protecting pedestriansdisposed along a vehicle transverse direction and which is formed by afoam for absorbing impact energy, characterized in that across-sectional configuration which is orthogonal to the longitudinaldirection of the bumper absorber for protecting pedestrians is formedinto a W shape having a portion in which a front notch portion notchedfrom a vehicle front side and rear notch portions notched from a vehiclerear side overlap with one another in a vehicle vertical direction.

Therefore, when, at the time of the collision, a load having apredetermined value or higher is applied from the vehicle front, thefront notch portion and the rear notch portions of the bumper absorberwhose cross-sectional configuration which is orthogonal to thelongitudinal direction of the bumper absorber is formed into a W shape,are opened, and the upper wall portion and the lower wall portion of thebumper absorber extend in the vehicle vertical direction. Accordingly,the upper wall portion and the lower wall portion of the bumper absorberare not compressed and deformed in the vehicle longitudinal direction.As a result, a rise in an impact load applied by the bumper absorber ona body into which the vehicle collides (i.e., a pedestrian who is hit bya bumper) can be controlled.

Each of the bumper absorber further comprises opening controlling meansfor controlling opening of the upper wall portion and the lower wallportion at an initial stage when a load is applied from the vehiclefront to the bumper absorber.

Accordingly, at an initial stage when a load is applied from the vehiclefront to the bumper absorber, with an operation of the openingcontrolling means, opening of the upper wall portion and the lower wallportion can be suppressively controlled. Consequently, an initial risein load level applied from the vehicle front to the bumper absorber canbe made higher than in a case in which opening controlling means is notformed.

In the bumper absorbers, the opening controlling means are at least ribsthat are formed so as to be separated from each other at predeterminedintervals in a longitudinal direction of the notches at the vehicle rearside, and the ribs are broken when the upper wall portion and the lowerwall portion are bent and deformed to a predetermined amount.

Therefore, at an initial stage when a load is applied from the vehiclefront to the bumper absorber, with an operation of at least the ribswhich are formed so as to be separated from one another in alongitudinal direction of the notches at the vehicle rear side, openingof the upper wall portion and the lower wall portion can besuppressively controlled. Thereafter, when the upper wall portion andthe lower wall portion are bent and deformed to a predetermined amount,the ribs are broken. Consequently, an initial rise in load level appliedfrom the vehicle front to the bumper absorber can be made higher than ina case in which the ribs are not formed.

In the bumper absorbers, the opening controlling means is a fixing meansfor fixing the upper wall portion and the lower wall portion to a bumperreinforcement, and fixing by the fixing means is released when the upperwall portion and the lower wall portion are bent and deformed to apredetermined amount.

Therefore, at an initial stage when a load is applied from the vehiclefront to the bumper absorber, with an operation of the fixing means forfixing the upper wall portion and the lower wall portion to the bumperreinforcement, opening of the upper wall portion and the lower wallportion can be suppressively controlled and thereafter, fixing isreleased when the upper wall portion and the lower wall portion are bentand deformed to a predetermined amount. Consequently, an initial rise inload level applied from the vehicle front to the bumper absorber can bemade higher than in a case in which a fixing means is not provided.

Each of the bumper absorbers further comprises a groove which is formedfrom a side opposite to the front notch.

Therefore, since, at an initial stage of the deformation of the bumperabsorber, a bending load is easily generated at a portion opposite tothe front notch portion starting from the groove, an initial rise in aload level can be increased. Further, in the final stages of thedeformation of the bumper absorber, due to an extension of the portionat which the groove is formed, a remaining thickness of the bumperabsorber which has been compressed is reduced, and in consequence, thetiming at which a bottoming load is generated can be delayed.

In the bumper absorbers, a cutting edge angle of the front notch portionand those of each of the rear notch portions are from 10° to 15°.

Since a cutting edge angle of the front notch portion and those of eachof the rear notch portions are from 10° to 15°, an initial rise in aload level can be made higher and the timing at which a bottoming loadis generated can be delayed.

Each of the bumper absorbers further comprises convex portions which areformed at an inside of each of the rear notch portions and which arepressed and broken by the bumper reinforcement when a load having apredetermined value or higher is applied from the vehicle front to thebumper absorber.

Since the convex portions which are formed at an inside of each of therear notch portions are pressed by the bumper reinforcement, the initialrise in load level can be increased. Further, in the final stages of thedeformation of the bumper absorber, when the convex portions formed atthe inside of each of the rear notch portions are pressed and broken bythe bumper reinforcement, the rear notch portions extend, and remainingthickness of the bumper absorber which has been compressed is reduced,whereby the timing at which a bottoming load is generated can bedelayed.

In the bumper absorbers, a width of each of the ribs is from 5 mm to 10mm and intervals between the ribs are from 30 mm to 50 mm.

Since a width of each of the ribs is from 5 mm to 10 mm and intervalsbetween the ribs are from 30 mm to 50 mm, energy absorbing performancecan be improved.

In the bumper absorbers, orientations of W shapes in a front-reardirection of the bumper absorber are inverted at predetermined intervalsin the vehicle transverse direction.

Accordingly, at an initial stage when a load is applied to the bumperabsorber for protecting pedestrians, the load is applied to the bumperabsorber in a direction in which some W shapes extend and the rest ofthe W shapes contract. Consequently, at a connecting portion on aboundary portion between the adjacent inverted W shapes, a shearingforce is generated. For this reason, an initial rise in load level canbe increased.

In the bumper absorbers, a boundary surface of an inverted W shape isinclined in a direction in which the inverted W shape is removed from amold.

The boundary surface of the inverted W shape is inclined in a directionin which the inverted W shape is removed from a mold, and thus removalof the absorber from the mold is facilitated. As a result, the bumperabsorber can be manufactured with a simple mold structure in whichordinary upper and lower molds are used and use of a slide cam is notrequired.

Another embodiment of the present invention is a bumper absorber forprotecting pedestrians, which is disposed in a bumper cover with alongitudinal direction of the bumper absorber for protecting pedestriansdisposed along a vehicle transverse direction and which is formed by afoam for absorbing impact energy, characterized in that across-sectional configuration which is orthogonal to the longitudinaldirection of the bumper absorber for protecting pedestrians is formedinto a zigzag shape having a portion in which a front notch portionnotched from a vehicle front side and rear notch portions notched from avehicle rear side overlap with one another in a vehicle verticaldirection, and orientations of zigzag shapes in a longitudinal directionare inverted at predetermined intervals in the vehicle transversedirection.

Thus, at an initial stage when a load is applied to the bumper absorberfor protecting pedestrians, the load is applied to the bumper absorberin a direction in which some zigzag shapes extend, and the rest of thezigzag shapes contract. Consequently, a shearing force is generated at aconnecting portion of a boundary portion between the adjacent invertedzigzag shapes, and for this reason, an initial rise in load level can bemade higher.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an enlarged cross sectional view (taken along a line 1-1 inFIG. 3) of a bumper absorber for protecting pedestrians according to afirst embodiment of the present invention;

FIG. 2 is a perspective view of the bumper absorber for protectingpedestrians according to the first embodiment of the present inventionas seen from a vehicle diagonal rear;

FIG. 3 is a perspective view of a vehicle body seen from a vehiclediagonal front, in which vehicle the bumper absorber for protectingpedestrians according to the first embodiment of the present inventionis adopted;

FIGS. 4A to 4D are operational explanatory views of the bumper absorberfor protecting pedestrians according to the first embodiment of thepresent invention;

FIG. 5 is a graph of load characteristics of the bumper absorber forprotecting pedestrians according to the first embodiment of the presentinvention;

FIG. 6 is a cross-sectional view corresponding to FIG. 1 and showing abumper absorber for protecting pedestrians according to a secondembodiment of the present invention;

FIG. 7 is a cross-sectional view corresponding to FIG. 1 and showing thebumper absorber for protecting pedestrians according to a modifiedexample of the second embodiment of the present invention;

FIG. 8A is a cross-sectional side view of a bumper absorber forprotecting pedestrians according to a third embodiment of the presentinvention, and FIGS. 8B and 8C are operational explanatory viewscorresponding to FIG. 8A and showing the bumper absorber for protectingpedestrians according to the third embodiment of the present invention;

FIG. 9 is a graph of load characteristics of the bumper absorber forprotecting pedestrians according to the third embodiment of the presentinvention;

FIG. 10 is a cross-sectional side view of a bumper absorber forprotecting pedestrians according to a fourth embodiment of the presentinvention;

FIG. 11A is a partial cross-sectional perspective view in which a bumperabsorber for protecting pedestrians according to a fifth embodiment ofthe present invention is seen from a vehicle diagonal front, and FIGS.11B and 11C are operational explanatory views corresponding to FIG. 11Aand showing the bumper absorber for protecting pedestrians according tothe fifth embodiment of the present invention;

FIG. 12 is a graph of load characteristics of the bumper absorber forprotecting pedestrians according to the fifth embodiment of the presentinvention;

FIG. 13 is a partial cross-sectional perspective view of a bumperabsorber for protecting pedestrians according to a modified example ofthe fifth embodiment of the present invention, as seen from a vehiclediagonal front;

FIG. 14 is a perspective view of a bumper absorber for protectingpedestrians according to a sixth embodiment of the present invention, asseen from a vehicle diagonal rear;

FIG. 15 is a graph of load characteristics of the bumper absorber forprotecting pedestrians according to the sixth embodiment of the presentinvention;

FIG. 16 is a cross-sectional view corresponding to FIG. 1 and showing abumper absorber for protecting pedestrians according to a seventhembodiment of the present invention;

FIG. 17 is a cross-sectional view which corresponds to FIG. 1 andshowing a bumper absorber for protecting pedestrians according to aneighth embodiment of the present invention;

FIG. 18 is a cross-sectional view corresponding to FIG. 1 and showing abumper absorber for protecting pedestrians according to a ninthembodiment of the present invention;

FIG. 19A is a plan view of a bumper absorber for protecting pedestriansaccording to a tenth embodiment of the present invention, FIG. 19B is afront view of the bumper absorber for protecting pedestrians of FIG.19A, and FIG. 19C is a side view of the bumper absorber for protectingpedestrians of FIG. 19A;

FIG. 20 is a perspective view of a bumper absorber for protectingpedestrians according to an eleventh embodiment of the presentinvention, as seen from a vehicle diagonal front;

FIG. 21 is an enlarged cross-sectional view taken along a line 2-2 inFIG. 20;

FIG. 22 is an enlarged cross-sectional view (taken along a line 3-3 inFIG. 24) of the bumper absorber for protecting pedestrians according tothe eleventh embodiment of the present invention;

FIG. 23 is an enlarged cross-sectional view (taken along a line 4-4 inFIG. 24) of the bumper absorber for protecting pedestrians according tothe eleventh embodiment of the present invention;

FIG. 24 is a perspective view of a vehicle body seen from a vehiclediagonal front, in which vehicle the bumper absorber for protectingpedestrians according to the eleventh embodiment of the presentinvention is adopted;

FIG. 25 is a graph of load characteristics of the bumper absorber forprotecting pedestrians according to the eleventh embodiment of thepresent invention;

FIG. 26 is a perspective view of a bumper absorber for protectingpedestrians according to a twelfth embodiment of the present invention,as seen from a vehicle diagonal front;

FIG. 27 is an enlarged cross-sectional view taken along a line 8-8 inFIG. 26; and

FIG. 28 is a schematic cross-sectional view of a conventional bumperabsorber for protecting pedestrians.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT First Embodiment

With reference to FIGS. 1 to 5, a bumper absorber for protectingpedestrians according to a first embodiment of the present inventionwill be explained hereinafter.

In these figures, arrow “UP” indicates an upper direction of a vehicle(hereinafter, “vehicle upper direction”), and arrow FR indicates a frontdirection of the vehicle (hereinafter, “vehicle front direction”).

As shown in FIG. 3, in the present embodiment, a front bumper 12 isdisposed at a lower front end portion of a vehicle body 10 of anautomobile in a vehicle transverse direction.

As shown in FIG. 1, a bumper reinforcement 14 of the front bumper 12 isdisposed in the vehicle transverse direction. A cross-sectionalconfiguration of the bumper reinforcement 14 as taken along a directionwhich is orthogonal to a longitudinal direction of the bumperreinforcement 14, that is, as seen from the vehicle transversedirection, is formed into a configuration having two portions i.e., anupper rectangular closed-cross-sectional portion 16 and a lowerrectangular closed-cross-sectional portion 18 which are connected toeach other by a front wall portion 14A.

A bumper absorber for protecting pedestrians 20 is disposed at a vehiclefront side of the front wall portion 14A of the bumper reinforcement 14in the vehicle transverse direction. A cross-sectional configuration ofthe bumper absorber for protecting pedestrians 20 as taken along adirection which is orthogonal to a longitudinal direction of the bumperabsorber for protecting pedestrians 20, that is, as seen from a vehicletransverse direction, is formed into a W shape having a portion in whicha front notch portion 22, which is notched from a vehicle front side,and an upper rear notch portion 24 and a lower rear notch portion 26,which are notched from a vehicle rear side, overlap with one another ina vehicle vertical direction. A length L expresses the portionoverlapped by the front notch portion 22, and the upper rear notchportion 24 and the lower rear notch portion 26.

The bumper absorber for protecting pedestrians 20 is constituted bymaterials which exhibit both excellent compressive strength and bendingstrength and are thus able to absorb impact energy. Examples of suchmaterials include a synthetic resin foam such as a polystyrene resin, apolyethylene resin, a polypropylene resin, a polyester resin, a styrenemodified polyethylene resin and the like. In particular, use of a moldproduct of a styrene modified polyethylene resin (styrene content: 50 to70 wt. %) bead foam is preferable.

Further, ribs 30 as opening controlling means are formed at the upperrear notch portion 24 and the lower rear notch portion 26, respectively,of the bumper absorber for protecting pedestrians 20, and triangularnotches 32 are formed from the vehicle rear side at the respective ribs30.

As shown in FIG. 2, the ribs 30 are formed in the upper rear notchportion 24 and the lower rear notch portion 26 so as to be spaced apartfrom each other at predetermined intervals in a longitudinal directioni.e., the vehicle transverse direction.

As shown in FIG. 1, the bumper reinforcement 14 and the bumper absorberfor protecting pedestrians 20 are covered with a bumper cover 36. Afront wall portion 36A of the bumper cover 36 and a front wall portion20A of the bumper absorber for protecting pedestrians 20 face eachother. Further, a rear wall portion 20B of the bumper absorber forprotecting pedestrians 20 abuts the front wall portion 14A of the bumperreinforcement 14. An upper wall portion 20C and a lower wall portion 20Dof the bumper absorber for protecting pedestrians 20 are inclinedportions that respectively correspond to an upper portion and a lowerportion of the W shape.

Next, an operation of the present embodiment will be explained.

In the present embodiment, when a pedestrian is hit by the front bumper12, a load is applied from the vehicle front via the front wall portion36A of the bumper cover 36 to the bumper absorber for protectingpedestrians 20. At this point, as shown in FIG. 4A, at an initial stagewhen the load is applied to the bumper absorber for protectingpedestrians 20, as a result of a reaction of the ribs 30 which arerespectively formed at the upper rear notch portion 24 and the lowerrear notch portion 26, opening of the upper wall portion 20C and thelower wall portion 20D of the bumper absorber for protecting pedestrians20 or, in other words, an extension of the upper wall portion 20C in avehicle upper direction (direction of arrow A) and an extension of thelower wall portion 20D in a vehicle lower direction (direction of arrowB), can be suppressively controlled.

Consequently, the upper wall portion 20C and the lower wall portion 20Dof the bumper absorber for protecting pedestrians 20 flex as shown, forexample, in FIG. 4B.

For this reason, as shown by a solid line in FIG. 5, the rise in loadlevel at an initial stage when an impact load is applied from thevehicle front to the bumper absorber for protecting pedestrians 20becomes higher than in the case shown by a broken line in FIG. 5 inwhich the ribs 30 are not formed at the bumper absorber.

Thereafter, when, as shown in FIG. 4C, the upper wall portion 20C andthe lower wall portion 20D of the bumper absorber for protectingpedestrians 20 are bent and deformed to a predetermined amount, each rib30 is broken, starting with notches 32. Consequently, the upper wallportion 20C extends in the vehicle upper direction (direction of arrowA) and the lower wall portion 20D extends in the vehicle lower direction(direction of arrow B), so that the bumper absorber for protectingpedestrians 20 opens, as shown in FIG. 4D. Then, when the bumperabsorber 20 is compressed over its wall thickness, the load isincreased.

Accordingly, since the upper wall portion 20C and the lower wall portion20D of the bumper absorber for protecting pedestrians 20 are notcompressed and deformed in the vehicle longitudinal direction, thecharacteristics of an impact load applied by the bumper absorber forprotecting pedestrians 20 on a pedestrian hit by the bumper are asexpressed by a solid line in FIG. 5. Accordingly, it is noteworthy thatthe compression rate at the second-half rise position S1 of an impactload in the case of the bumper absorber 20 is higher than thecompression rate at the second-half rise position S2 thereof in the casewhich is shown by a double-dashed line in FIG. 5, in which a bumperabsorber for protecting pedestrians having a rectangular cross sectionalconfigurations used, and also that a load value T1 at the position S1 issmaller than a load value T2 at the position S2.

The dashed line of FIG. 5 expresses load characteristics in a case inwhich a material density of the bumper absorber for protectingpedestrians having the rectangular cross-sectional configuration asshown by the double-dashed line in FIG. 5 is reduced to ½ (low density).It is noteworthy that a load value T3 at the position S2 is smaller thanthat of T2.

Accordingly, in the present embodiment, a second-half rise (bottoming)in an impact load acting on a pedestrian who is hit by a bumper can becontrolled, and in addition, an initial load can be increased.

Further, since the bumper absorber for protecting pedestrians 20 isstructured as described above in the present embodiment, a performancethat is requested for protecting pedestrians at respective portions inthe vehicle transverse direction (vehicle center portion or vehicle sideportions) of the bumper absorber for protecting pedestrians 20 can berealized only by making local changes on the configuration of the Wshape, or on configurations and/or intervals of the rib 30 at therespective portions. Accordingly, there is no need for a fundamentalchange of configuration nor for a degree of forming of the bumperabsorber for protecting pedestrians 20.

Second Embodiment

Next, with reference to FIG. 6, a bumper absorber for protectingpedestrians according to a second embodiment of the present inventionwill be explained.

Portions identical to those in the first embodiment of the presentinvention will be denoted by the same reference numerals and adescription thereof will therefore be omitted.

As shown in FIG. 6, in the present embodiment instead of the ribs 30according to the first embodiment of the present invention, engagingprotrusions 40 are formed as opening controlling means (fixing means),respectively at the upper portion and the lower portion of the rear wallportion 20B of the bumper absorber for protecting pedestrians 20.Further, these engaging protrusions 40 are engaged with engaging holes42 which are formed respectively at the upper portion and the lowerportion of the front wall portion 14A of the bumper reinforcement 14.When the upper wall portion 20C and the lower wall portion 20D of thebumper absorber for protecting pedestrians 20 are bent and deformed to apredetermined amount, the engagement between the engaging protrusions 40and the engaging holes 42 is released.

Next, an operation of the present embodiment will be explained.

In the present embodiment, when a pedestrian is hit by the front bumper12, a load is applied from the vehicle front via the front wall portion36A of the bumper cover 36 to the bumper absorber for protectingpedestrians 20. At this point, at an initial stage when a load isapplied to the bumper absorber for protecting pedestrians 20, with anengagement of the engaging protrusions 40 of the bumper absorber forprotecting pedestrians 20 with the engaging holes 42 of the bumperreinforcement 14, opening of the upper wall portion 20C and the lowerwall portion 20D of the bumper absorber for protecting pedestrians 20,namely, an extension of the upper wall portion 20C in the vehicle upperdirection and an extension of the lower wall portion 20D in the vehiclelower direction can suppressively be controlled.

Consequently, the upper wall portion 20C and the lower wall portion 20Dof the bumper absorber for protecting pedestrians 20 flex. Therefore, asshown by a solid line in FIG. 5, a rise in load level at an initialstage when the load is applied from the vehicle front to the bumperabsorber for protecting pedestrians 20 becomes higher than in the caseshown by a broken line in FIG. 5 in which the engaging protrusions 40and the engaging holes 42 are not formed.

Thereafter, when the upper wall portion 20C and the lower wall portion20D of the bumper absorber for protecting pedestrians 20 are bent anddeformed by a predetermined amount, the engagement between the engagingprotrusions 40 of the bumper absorber for protecting pedestrians 20 andthe engaging holes 42 of the bumper reinforcement 14 is released. As aresult, the upper wall portion 20C extends in the vehicle upperdirection and the lower wall portion 20D extends in the vehicle lowerdirection, and the bumper absorber for protecting pedestrians 20 isopened.

In consequence, the upper wall portion 20C and the lower wall portion20D of the bumper absorber for protecting pedestrians 20 are notcompressed and deformed in the vehicle longitudinal direction, and thecharacteristics of an impact load applied by the bumper absorber forprotecting pedestrians 20 on a pedestrian are expressed by a solid linein FIG. 5. It is noteworthy that the compression rate at the second-halfrise position S1 of an impact load in the case of the bumper absorber ofthe present embodiment is higher than the compression rate at thesecond-half rise position S2 of the impact load in the case shown by adouble-dashed line in FIG. 5 in which the bumper absorber for protectingpedestrians having a rectangular cross sectional configuration is used,and that a load value T1 at the position S1 is smaller than a load valueT2 at the position S2.

Accordingly, in the present embodiment, a second-half rise (bottoming)in an impact load acting on a pedestrian who is hit by a bumper can becontrolled, and in addition, an initial load can be increased.

Further, since, in the present embodiment, the bumper absorber forprotecting pedestrians 20 is structured as described above, aperformance capability demanded for protecting pedestrians at respectiveportions in the vehicle transverse direction (vehicle center portion orvehicle side portions) of the bumper absorber for protecting pedestrians20 can be realized only by making local changes on the configuration ofthe W shape. Accordingly, there is no need for a fundamental change ofconfiguration nor for a degree of foaming of the bumper absorber forprotecting pedestrians 20.

In the present embodiment, the engaging protrusions 40 of the bumperabsorber for protecting pedestrians 20 and the engaging holes 42 of thebumper reinforcement 14 are engaged with each other. However, instead,as shown in FIG. 7, adhesives 46 can be used as the opening controllingmeans (fixing means) to adhere the upper portion of the rear wallportion 20B of the bumper absorber for protecting pedestrians 20 withthe upper portion of the front wall portion 14A of the bumperreinforcement 14, and to adhere the lower portion of the rear wallportion 20B of the bumper absorber for protecting pedestrians 20 withthe lower portion of the front wall portion 14A of the bumperreinforcement 14. When the upper wall portion 20C and the lower wallportion 20D of the bumper absorber for protecting pedestrians 20 arebent and deformed to a predetermined amount, the portions adhered by theadhesives 46 can be broken.

Third Embodiment

With reference to FIGS. 8A to 8C and FIG. 9, a third embodiment of thepresent invention of a bumper absorber for protecting pedestrians willbe explained, hereinafter.

Portions identical to those in the first embodiment of the presentinvention will be denoted by the same reference numerals and adescription thereof will be omitted.

In the present embodiment, as shown in FIG. 8A, at a linking portion forlinking an intermediate wall portion 20E and an intermediate wallportion 20F to one another, a groove 70 having a V-shapedcross-sectional configuration is formed in the vehicle transversedirection so as to oppose the front notch portion 22 (as seen from thebumper reinforcement 14 side) at a central vertical directional centralportion of the rear wall portion 20B. The intermediate wall portion 20Eand the intermediate wall portion 20F are disposed between the upperwall portion 20C and the lower wall portion 20D of the bumper absorberfor protecting pedestrians 20.

Next, an operation of the present embodiment will be explained.

In the same manner as in the first embodiment of the present invention,when a pedestrian is hit by the front bumper 12, a load is applied fromthe vehicle front via the front wall portion 36A of the bumper cover 36to the bumper absorber for protecting pedestrians 20. At this time, inthe present embodiment, at an initial stage when a load is applied tothe bumper absorber for protecting pedestrians 20, as shown in FIG. 8B,at a central portion in the vertical directional of the rear wallportion 20B of the bumper absorber for protecting pedestrians 20, abending load F1 is easily generated at the intermediate wall portions20E and 20F of the bumper absorber for protecting pedestrians 20,starting from the groove 70 which has been formed from a side oppositeto the front notch portion 22. For this reason, a rise in the initialload level can be increased.

In the final stages of the deformation of the bumper absorber, as shownin FIG. 8C, the rear wall portion 20B, at which the groove 70 is formed,extends in the vertical direction (direction of arrow H), and aremaining thickness M of the bumper absorber for protecting pedestrians20 which has been compressed, is reduced. Accordingly, the timing atwhich a bottoming load is generated can be delayed.

For this reason, in the present embodiment, as shown by a solid line inFIG. 9, the rise in an impact load at an initial stage when the impactload is applied from the vehicle front to the bumper absorber forprotecting pedestrians 20 can be made higher than in the case shown by adouble-dashed line in FIG. 9 in which the groove 70 is not formed.Further, the compression rate at the second-half rise position S1 of theimpact load in the base of the bumper absorber 20 is higher than thecompression rate at the second-half rise position S2 in the case shownby the double-dashed line in FIG. 9 in which the groove 70 is notformed.

Accordingly, in the present embodiment, a second-half rise (bottoming)of an impact load acting on a pedestrian who is hit by a bumper can becontrolled, and an initial load can be increased.

Further, in the present embodiment, the groove 70 is formed into aV-shaped cross-sectional configuration. However, the present inventionis not limited to this, and instead, the groove 70 can be formed intoanother cross-sectional configuration such as a U shape or the like.

Fourth Embodiment

Next, as shown in FIG. 10, a bumper absorber for protecting pedestriansaccording to a fourth embodiment of the present invention will beexplained.

Portions identical to those in the first embodiment of the presentinvention will be denoted by the same reference numerals and adescription thereof will be omitted.

As shown in FIG. 10, in the present embodiment, a cutting edge angle θ1of the front notch portion 22 of the bumper absorber for protectingpedestrians 20 is from 10° to 15°, and a cutting edge angle θ2 of eachof the upper rear notch portion 24 and the lower rear notch portion 26of the bumper absorber for protecting pedestrians 20 is also from 10° to15°.

Next, an operation of the present embodiment will be explained.

In the same manner as in the first embodiment of the present invention,when a pedestrian is hit by the front bumper 12, a load is applied fromthe vehicle front via the front wall portion 36A of the bumper cover 36to the bumper absorber for protecting pedestrians 20. At this time, inthe present embodiment, since the cutting edge angle θ1 of the frontnotch portion 22, and the cutting edge angle θ2 of each of the upperrear notch portion 24 and the lower rear notch portion 26 have been setat less than 15°, at an initial stage when a load is applied to thebumper absorber for protecting pedestrians 20, the bumper absorber forprotecting pedestrians 20 is not easily deformed, and an initial rise inload level can be increased.

In the present embodiment the cutting edge angle θ1 of the front notchportion 22, and the cutting edge angle θ2 of each of the upper rearnotch portion 24 and the lower rear notch portion 26 have been set atmore than 10°. Accordingly, in the final stages of the deformation ofthe bumper absorber, a remaining thickness of the bumper absorber forprotecting pedestrians 20 which has been compressed, is reduced, and thetiming at which a bottoming load is generated can be delayed.

Thus, in the present embodiment, a rise in the impact load at an initialstage when the impact load is applied from the vehicle front to thebumper absorber for protecting pedestrians 20 can be made higher thanthat in a case in which the cutting edge angle θ1 of the front notchportion 22 and the cutting edge angle θ2 of each of the upper rear notchportion 24 and the lower rear notch portion 26 have not been set withinan angle range of from 10° to 15°. Here, a second-half rise position ofthe impact load corresponds to a position at which a compression rate ishigh.

Accordingly, in the present embodiment, a second-half rise (bottoming)in an impact load acting on a pedestrian who is hit by a bumper can becontrolled, and an initial load can be increased.

Fifth Embodiment

Next, with reference to FIGS. 11A to 11C, and FIG. 12, a bumper absorberfor protecting pedestrians according to a fifth embodiment of thepresent invention will be explained.

Portions identical to those in the first embodiment of the presentinvention will be denoted by the same reference numerals and adescription thereof will be omitted.

As shown in FIG. 11A, in the bumper absorber for protecting pedestrians20 according to the present embodiment, horn portions 20G are formed asconvex portions such that one of the horn portions 20G is formed at theinside of the upper rear notch portion 24 so as to extend in the vehicletransverse direction from an end portion at the rear wall portion 20Bside of the upper wall portion 20C, and the other horn portion 20G isformed at the inside of the lower rear notch portion 26 so as to extendin the vehicle transverse direction from an end portion at the rear wallportion 20B of the lower wall portion 20D.

Further, an upper end edge portion 14B and a lower end edge portion 14Cof the front wall portion 14A of the bumper reinforcement 14 abut thehorn portions 20G of the bumper absorber for protecting pedestrians 20,respectively.

As shown in FIG. 11B, when a load having a predetermined value or higheris applied from the vehicle front to the bumper absorber for protectingpedestrians 20, the horn portions 20G of the bumper absorber forprotecting pedestrians 20 are pressed and broken by the bumperreinforcement 14.

Next, an operation of the present embodiment will be explained.

In the same manner as in the first embodiment of the present invention,when a pedestrian is hit by the front bumper 12, a load is applied fromthe vehicle front via the front wall portion 36A of the bumper cover 36to the bumper absorber for protecting pedestrians 20. At this point, asshown in FIG. 11A, at an initial stage when the load is applied to thebumper absorber for protecting pedestrians 20, since the upper end edgeportion 14B and the lower end edge portion 14C of the front wall portion14A of the bumper reinforcement 14 respectively abut the horn portions20G of the bumper absorber for protecting pedestrians 20, a bending loadis easily generated at the upper wall portion 20C and the lower wallportion 20D, respectively, of the bumper absorber for protectingpedestrians 20, starting from each of the horn portions 20G.Accordingly, an initial rise in load level can be increased.

Further, in the final stages of the deformation of the bumper absorber,as shown in FIG. 11B, the horn portions 20G of the bumper absorber forprotecting pedestrians 20 are pressed and broken by the bumperreinforcement 14. For this reason, the bumper reinforcement 14 entersbetween the upper wall portion 20C and the lower wall portion 20D of thebumper absorber for protecting pedestrians 20, and as shown in FIG. 11C,the upper wall portion 20C and the lower wall portion 20D extendrespectively in the vertical direction (direction of arrow H).Therefore, a remaining thickness of the bumper absorber for protectingpedestrians 20 which has been compressed, is reduced and the timing atwhich a bottoming load is generated can be delayed.

In the present embodiment, as shown by a solid line in FIG. 12, a risein the impact load at an initial stage when the impact load is appliedfrom the vehicle front to the bumper absorber for protecting pedestrians20 can be made higher than that in the case which is shown by adouble-dashed line in FIG. 12 in which the horn portions 20G are notformed. Further, the compression rate at the second-half rise positionS1 of the impact load in the case of the bumper absorber 20 is higherthan the compression rate at a broken point P of the horn portions 20G.Accordingly, the compression rate of the second-half rise position S1 inthe case of the bumper absorber 20 is higher than the compression rateat the second-half rise position S2 of the impact load in a case inwhich the horn portions 20G are not formed.

Accordingly, in the present embodiment, a second-half rise (bottoming)in an impact load acting on a pedestrian who is hit by a bumper can becontrolled, and an initial load can be increased.

Moreover, in the present embodiment, the horn portions 20G are formed asconvex portions at the bumper absorber for protecting pedestrians 20.However, the convex portions are not limited to the horn portions 20D,and instead, as shown in FIG. 13, other convex portions such as ribs 20Hwhich are formed in the vehicle transverse direction so as to be apartfrom one another at predetermined intervals can be formed at the bumperabsorber for protecting pedestrians 20.

Sixth Embodiment

Next, with reference to FIG. 14 and FIG. 15, a bumper absorber forprotecting pedestrians according to a sixth embodiment of the presentinvention will be explained.

Portions identical to those in the first embodiment of the presentinvention will be denoted by the same reference numerals and adescription thereof will be omitted.

As shown in FIG. 14, in the present embodiment, a width W of one rib 30at the bumper absorber for protecting pedestrians 20 is 5 mm to 10 mm,and each distance P between the ribs 30 is 30 mm to 50 mm.

Next, an operation of the present embodiment will be explained.

In the present embodiment, as shown in FIG. 15, the width W of one rib30 at the bumper absorber for protecting pedestrians 20 is 5 mm to 10mm, and the distance P between the ribs 30 is 30 mm to 50 mm. As aresult, when the compression rate in the vehicle longitudinal directionof the bumper absorber for protecting pedestrians 20 is 50%, therequired impact load value T1 of the present embodiment is increased byabout 40% more than the impact load value T2 required in the case whenthe ribs 30 are not formed at the bumper absorber for protectingpedestrians 20. Accordingly, energy absorbing performance can beimproved.

In the above description, a more detailed description of the specifiedembodiments of the present invention has been given. However, thepresent invention is not limited to these embodiments. It is apparentfor those skilled in the art that various other embodiments can beenabled as long as they are within the spirit of the invention. Suchembodiments will be explained with reference to the seventh to twelfthembodiments, which follow.

Seventh Embodiment

As shown in FIG. 16, the bumper absorber for protecting pedestrians 20can be structured such that an orientation of the bumper absorber forprotecting pedestrians 20 in the vehicle longitudinal direction isinverted.

Eighth Embodiment

In each of the above-described embodiments, a cross-sectionalconfiguration, as taken along a direction which is orthogonal to alongitudinal direction of the bumper absorber for protecting pedestrians20, is formed into a W shape having a portion in which the front notchportion 22, notched from the vehicle front side, and the upper rearnotch portion 24 and the lower rear notch portion 26, notched from thevehicle rear side, overlap with one another in the vehicle verticaldirection. However, the cross section of the bumper absorber forprotecting pedestrians 20 is not limited to the W shape.

Accordingly, as shown in FIG. 17, the cross-sectional configuration ofthe bumper absorber for protecting pedestrians 20, as taken along adirection orthogonal to a longitudinal direction of the bumper absorber,can be formed into a zigzag shape.

Ninth Embodiment

As shown in FIG. 18, the cross-sectional configuration of the bumperabsorber for protecting pedestrians 20, as taken along a directionorthogonal to a longitudinal direction of the bumper absorber, can beformed into a crank shape having a portion in which the front notchportion 22, notched from the vehicle front side, and the upper rearnotch portion 24 and the lower rear notch portion 26, notched from thevehicle rear side, overlap with one another in the vehicle verticaldirection.

In this case, further, an inclination surface 50 can be formed asopening means at a portion at which the upper wall portion 20C and thelower wall portion 20D of the bumper absorber for protecting pedestrians20 abut the front wall portion 14A of the bumper reinforcement 14. Whena load having a predetermined value or higher is applied from thevehicle front to the bumper absorber for protecting pedestrians 20, theinclination surface 50 moves the upper wall portion 20C of the bumperabsorber for protecting pedestrians 20 in the vehicle upper directionand the lower wall portion 20D of the bumper absorber for protectingpedestrians 20 in the vehicle lower direction, respectively, and, inother words, opens the upper wall portion 20C and the lower wall portion20D in the vehicle vertical direction.

Tenth Embodiment

As shown in FIGS. 19A to 19C, in order to contribute to boosting a risein the level of load applied at an initial stage and an increase in animpact absorbing amount after the upper wall portion 20C and the lowerwall portion 20D have been opened in the vehicle vertical direction, aplurality of convex portions 60 can be formed at the upper side of theupper wall portion 20C and the lower side of the lower wall portion 20Dof the bumper absorber for protecting pedestrians 20 so as to be spacedapart from each other in the vehicle transverse direction atpredetermined intervals.

Eleventh Embodiment

Next, with reference to FIGS. 20 to 24, a bumper absorber for protectingpedestrians according to an eleventh embodiment of the present inventionwill be explained.

In these figures, arrow “UP” indicates a vehicle upper direction andarrow “FR” indicates a vehicle front direction. In addition, portionsidentical to those in the first embodiment of the present invention willbe denoted by the same reference numerals.

As shown in FIG. 24, in the present embodiment, the front bumper 12 isdisposed at the lower front end portion of the vehicle body 10 of anautomobile in the vehicle transverse direction.

As shown in FIG. 22, the bumper reinforcement 14 of the front bumper 12is disposed in the vehicle transverse direction. The cross section ofthe bumper reinforcement 14, as taken along a direction which isorthogonal to the longitudinal direction of the bumper reinforcement 14,i.e., as seen from the vehicle transverse direction, is formed into aconfiguration in which the two upper and lower rectangular closedcross-sectional portions 16 and 18 are connected by the front wallportion 14A. Further, the bumper absorber for protecting pedestrians 20is disposed at the vehicle front side surface of the front wall portion14A of the bumper reinforcement 14.

As shown in FIG. 20, the cross-sectional configuration of the bumperabsorber 20, as taken along the direction which is orthogonal to thelongitudinal direction of the bumper absorber (vehicle transversedirection), is formed into a W shape. The orientations of W shapes inthe front-rear direction of the bumper absorber are inverted in thevehicle transverse direction at predetermined intervals. Namely, in thebumper absorber for protecting pedestrians 20, ordinary portions 32 eachcorresponding to a length P1 in the vehicle transverse direction, andinverted portions 34 each corresponding to a length P2 in the vehicletransverse direction are alternately formed in the vehicle transversedirection.

As shown in FIG. 22, in an ordinary portion 32 of the bumper absorberfor protecting pedestrians 20, the cross sectional configuration of thebumper absorber 20 as seen from the vehicle transverse direction isformed into a W shape having a portion in which the front notch portion22 notched from the vehicle front side and the upper rear notch portion24 and the lower rear notch portion 26 notched from the vehicle rearside overlap with one another in the vehicle vertical direction, and thelength of the portion at which the front notch portion 22, and the upperrear notch portion 24 and the lower rear notch portion 26 overlap withone another is expressed by L.

As shown in FIG. 23, on the other hand, in the inverted portions 34 ofthe bumper absorber 20 for protecting pedestrians 20, thecross-sectional configuration of one inverted portion 34, as taken alongthe vehicle transverse direction, is formed into a W shape having aportion in which a rear notch portion 23, which is notched from thevehicle rear side, and an upper front notch portion 25 and a lower frontnotch portion 27, which are notched from the vehicle front side, overlapwith one another in the vehicle vertical direction, and the length ofthe portion at which the rear notch portion 23, and the upper frontnotch portion 25 and the lower front notch portion 27 overlap with oneanother is expressed by L.

Examples of materials used for the bumper absorber for protectingpedestrians 20 include the same materials as those described in thefirst embodiment of the present invention, and a description thereofwill be omitted.

As shown in FIGS. 22 and 23, the bumper reinforcement 14 and the bumperabsorber for protecting pedestrians 20 are covered with a bumper cover36′. A front wall portion 36′A of the bumper cover 36′ and a front wallportion 20A of the bumper absorber for protecting pedestrians 20 faceeach other. Further, a rear wall portion 20B of the bumper absorber forprotecting pedestrians 20 abuts the front wall portion 14A of the bumperreinforcement 14. An upper wall portion 20C and a lower wall portion 20Dof the bumper absorber for protecting pedestrians 20 are inclinedportions that respectively correspond to an upper portion and a lowerportion of the W shape.

Next, an operation of the present embodiment will be explained.

In the present embodiment, when a pedestrian is hit by the front bumper12, a load is applied from the vehicle front via the front wall portion36′A of the bumper cover 36′ to the bumper absorber for protectingpedestrians 20. At this point, as shown in FIG. 20, at an initial stagewhen the load is applied to the bumper absorber for protectingpedestrians 20, a load F is generated at the inverted portion 34 of thebumper absorber for protecting pedestrians 20 in a direction in whichthe upper wall portion 20C and the lower wall portion 20D extend (in thedirection of arrow A of FIG. 20). On the other hand, a load is generatedat the ordinary portion 32 of the bumper absorber for protectingpedestrians 20 in a direction in which a distance between the upper wallportion 20C and the lower wall portion 20D becomes narrower (directionof arrow B in FIG. 20).

As a result, as shown in FIG. 21, a shearing force is generated at aportion at which ordinary portions 32 and the inverted portion 34 of thebumper absorber for protecting pedestrians 20 intersect, namely, at aconnecting portion S of a boundary portion between the adjacent invertedW shapes (a hatched portion shown in FIG. 21).

For this reason, in the present embodiment, as shown by solid line inFIG. 25, an initial rise in load level when an impact load is appliedfrom the vehicle front to the bumper absorber for protecting pedestrians20 can be increased, and a decrease in an energy absorbing amount can beprevented, as compared to a case which is shown by a double-dashed linein FIG. 25 in which the orientations of the W shapes are not inverted atpredetermined intervals in the vehicle transverse direction, namely, ina case in which the bumper absorber for protecting pedestrians 20entirely comprises the ordinary portion 32.

In the final stages of the deformation of the bumper absorber, theconnecting portion S is broken by the shearing force, and the W shapeextends, causing a remaining thickness of the bumper absorber which hasbeen compressed to be reduced. Accordingly, the timing at which abottoming load is generated can be delayed, and a rise in the impactload acting on a pedestrian who is hit by a bumper can be controlled.

Twelfth Embodiment

With reference to FIGS. 26 and 27, a bumper absorber for protectingpedestrians 20 according to a twelfth embodiment of the presentinvention will be explained hereinafter.

Portions identical to those in the eleventh embodiment will be denotedby the same reference numerals and a description thereof will beomitted.

As shown in FIG. 26, in the present embodiment, a boundary wall portion80 between the ordinary portion 32 and the inverted portion 34 of thebumper absorber for protecting pedestrians 20 are inclined in adirection in which the bumper absorber is removed from a mold (indirections of arrow C and arrow D in FIG. 26).

As shown in FIG. 27, the boundary wall portions 80 of the bumperabsorber for protecting pedestrians 20 are inclined at an inclinationangle θ1 with respect to the forward removal direction (direction ofarrow C in FIG. 26) so as to prevent a hole from being formed in thevicinity of the boundary wall portion 80 when the bumper absorber isremoved from a mold in a forward direction. Further, the boundary wallportion 80 is inclined at an inclination angle θ2 (θ1=θ2) with respectto the rearward direction (direction of arrow D in FIG. 26) so as toprevent a hole from being formed in the vicinity of the boundary wallportion 80 when the bumper absorber is pulled out in a rearward removaldirection.

Accordingly, in the present embodiment, the bumper absorber can bemanufactured with a simple molding structure in which ordinary upper andlower molds are used, without using a slide cam. Accordingly, the bumperabsorber can be manufactured inexpensively.

In the eleventh and twelfth embodiments of the present inventiondescribed above, it is apparent for those skilled in the art thatvarious other modifications can be enabled without departing from thespirit of the invention. For example, in the twelfth embodiment, theinclination angle θ1 and the inclination angle θ2 have been made thesame (θ1=θ2). However, the inclination angle θ1 and the inclinationangle θ2 can be made different from each other (θ1≠θ2).

Further, in the eleventh and twelfth embodiments of the presentinvention described above, the cross sectional configuration of thebumper absorber 20, as taken along the direction which is orthogonal tothe longitudinal direction of the bumper absorber 20 (i.e., as seen fromthe vehicle transverse direction) is formed into a W shape. However, thecross sectional configuration of the bumper absorber 20, as taken alongthe direction which is orthogonal to the longitudinal direction of thebumper absorber (as seen from the vehicle transverse direction) is notlimited to the W shape, and instead, can be formed into another zigzagshape including a V shape.

INDUSTRIAL APPLICABILITY

The bumper absorber for protecting pedestrians according to the presentinvention exhibits excellent effects in that a load level rises swiftlyat an initial stage when a load is applied to a pedestrian hit by abumper, while a rise in impact load acting on the pedestrian who is hitby the bumper can be controlled.

1. A bumper absorber for protecting pedestrians, which is disposedinside a bumper cover with the longitudinal direction of the bumperabsorber for protecting pedestrians being disposed along a vehicletransverse direction and which is formed by a foam for absorbing impactenergy, characterized in that a cross-sectional configuration which isorthogonal to the longitudinal direction of the bumper absorber isformed into a W shape having a portion in which a front notch portion,which is notched from a vehicle front side, and a rear notch portion,which is notched from a vehicle rear side, overlap with one another in avehicle vertical direction.
 2. The bumper absorber according to claim 1,wherein orientations of W shapes in a front-rear direction of the bumperabsorber are inverted at predetermined intervals in the vehicletransverse direction.
 3. The bumper absorber according to claim 2,wherein boundary surfaces of the inverted W shapes are inclined in adirection in which the inverted W shapes are removed from a mold.
 4. Thebumper absorber according to claim 3, wherein boundary surfaces fordefining the front notch portion and the rear notch portion of theinverted W shapes are inclined in a direction in which the inverted Wshapes are removed from a mold such that the front notch portion and therear notch portion of the inverted W shapes are respectively notcommunicated with those of the W shapes adjacent to the inverted Wshapes in the longitudinal direction of the bumper absorber.